Heat transfer sheet

Abstract

PCT No. PCT/JP89/00877 Sec. 371 Date Apr. 30, 1990 Sec. 102(e) Date Apr. 30, 1990 PCT Filed Aug. 29, 1989 PCT Pub. No. WO90/02047 PCT Pub. Date Mar. 8, 1990.A heat transfer sheet according to the present invention includes a substrate sheet and a dye carrying layer formed on its one major side, and is characterized in that a dye included in the dye carrying layer is expressed by the following general formula (I) or (II): (* CHEMICAL STRUCTURE *) (I) (* CHEMICAL STRUCTURE *) (II) An image formed with such a heat transfer sheet shows excellent fastness properties, and excels in resistance to contamination in particular.

We claim: 
     
       1. A heat transfer sheet comprising a substrate sheet and a dye carrying layer formed on its major side, characterized in that a dye included in said dye carrying layer is expressed by the following general formula (II): ##STR9## wherein: A stands for a cyano, alkoxycarbonyl, aryloxycarbonyl, carbamoyl, alkylcarbamoyl, arylcarbamoyl, alkylcarbonyl, arylcarbonyl, alkylsulfonyl, alkylsulfonylamino, arylsulfonyl or aryl group, R 1  denotes a substituted or unsubstituted alkyl, aralkyl or aryl group, or an atom or atomic group which form a five- or six-membered ring together with Z,   R 2  indicates a substituted or unsubstituted alkyl, aralkyl or aryl group,   said R 1  and R 2  may form a five- or six-membered ring which may include an oxygen or nitrogen atom,   R 3  stands for a hydrogen or halogen atom or an alkyl, alkoxy or acylamino group which may include a substituent,   R 4  denotes a hydrogen or halogen atom or an alkyl, alkoxy, nitro, cyano, acylamino or aryl group which may include a substituent,   Z indicates a hydrogen atom or an atom or atomic group which forms a five- or six-membered ring together with R 1 , and   n and m each are 1 or 2.   
     
     
       2. A heat transfer sheet as recited in claim 1, wherein said dye has a molecular weight of at least 400. 
     
     
       3. A heat transfer sheet as recited in claim 1, wherein Z is a hydrogen atom, R 1  and/or R 2  are an ethyl group which may contain a hydroxyl group, R 3  is an alkyl or alkoxyl group located at the ortho-position with respect to the azomethyne group, R 4  is a hydrogen atom, A is a cyano or alkoxycarbonyl group, and m and n each are 1. 
     
     
       4. A heat transfer sheet as recited in claim 1, wherein at least one of said substituents R 1  -R 3  and A contains a polar group such as a hydroxyl, amino, alkylamino, acylamino, sulfonylamino, aminocarbonyl, aminosulfonyl, alkoxycarbonyl, alkoxysulfonyl, cyano, alkoxy, phenyl, cycloalkyl or nitro group or a halogen atom.